multi-object tracking

**Multi-Object Tracking (MOT)** is the **task of estimating the trajectory of multiple unique objects in a video** — assigning a unique ID to each detected object and maintaining that ID even as objects cross paths, are occluded, or move erratically. **What Is MOT?** - **Paradigm**: Detection-by-Tracking vs. Tracking-by-Detection. - **Standard Pipeline**: 1. **Detect** objects in current frame (YOLO). 2. **Extract** features (Re-ID embedding + Motion/Kalman Filter). 3. **Associate** with existing tracks (Hungarian Algorithm). - **Metric**: MOTA (Multiple Object Tracking Accuracy), IDF1. **Why It Matters** - **Traffic Monitoring**: Counting distinct cars, not just detections per frame. - **Crowd Analysis**: Tracking flow of people in public spaces. - **Retail**: Tracking customer paths through a store ("Customer Flow"). **Key Failure Mode**: **ID Switch**. When two people cross paths and the tracker swaps their IDs. **Multi-Object Tracking** is **converting perception into identity** — turning raw detections into persistent, trackable entities.